Boron diffusion in heavily implanted silicon thin films, deposited from disilane (Si2H6) via low-pressure chemical vapour deposition at low temperatures, was modelled. A 1-dimensional 2-stream diffusion model, tailored to the structure of deposited Si films and to the effects of high B concentrations, was developed. The model included B-clustering in grains as well as in grain boundaries. The effects of Si-film crystallization, during thermal post-implantation annealing, upon B diffusion as well as upon B cluster formation and dissolution, were included. The effects of clustering, grain growth, dopant-enhanced grain growth and the driving force for grain growth were coupled to the dopant diffusion coefficients and to the temperature using thermodynamic concepts. In order to investigate complex B diffusion in heavily-implanted Si films deposited by low-pressure chemical vapour deposition, experimental profiles were used which were obtained by secondary ion mass spectroscopy after 15keV B implantation to doses of 1015, 4 x 1015 or 5 x 1015/cm2. Post-implantation annealing was carried out at 700 or 850C for between 60s and 0.25h. A good agreement of the simulated profiles with the experimental secondary ion mass spectroscopy profiles validated the model. It was found that the simulation reproduced the experimental secondary ion mass spectroscopy profiles well when the growth of grains and immobile B clusters was considered. Modelling Boron Diffusion in Heavily Implanted Low-Pressure Chemical Vapor Deposited Silicon Thin Films during Thermal Post-Implantation Annealing. S.Abadli, F.Mansour: Thin Solid Films, 2009, 517[6], 1961-6